These accessor methods attempt to retrieve meta data from the source XML::RSS::Parser element by checking a list of potential tag names until one returns a value.
They are generally based on Dublin Core terminology and RSS elements that are common across the many formats.
If called in a SCALAR context,
the value of the first element of the tag being matched is returned.
If called in an ARRAY context it will return all of the values to the tag being matched -- it does not return all of the values for all of the tags that have been mapped to the method.
(Note that some mappings only allow one value to be returned.) Returns undef if nothing could be found.

The following are the tags (listed in XPath notation) mapped to each method and the order in which they are checked.